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91.
The synthesis of novel Co(I) polymers featuring CpCo(C(4)R(4)) units are reported. The cyclopentadienyl ring on the CpCo(C(4)R(4)) unit has been functionalized with acrylate or methacrylate groups. Acrylate derivatives of these compounds were found to polymerize giving rise to the first example of polymers containing neutral, 18 e cobaltoarenocenes in the side chain. 相似文献
92.
We report a class of water-soluble and -stable cyclic amino squarates that ligate with cysteine or lysine residues without side-products in an entirely aqueous environment. The ligations include addition-elimination reactions that are promoted by water in a way similar to S(N)1 reactions. The structural versatility of the reactants allows the potential recognition of selected amino acid residues on proteins. 相似文献
93.
The present paper focused on the detection of methanol and propanol using Pd-gate metal-oxide-semiconductor (MOS) sensor. Surface mor- phology and composition of the gate film were studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The response of the sensor for propanol and methanol was measured as shift in capacitance-voltage (C-V) and conductance-voltage (G-V) curves of the MOS structure. The sensitivity of the sensor towards methanol was found to be greater than that towards propanol. It was 58.2% for methanol and 32% for propanol (at 0.6 V, 1 MHz) in terms of capacitance measurements, while in terms of conductance results the sensitivity was found to be 57.2% for methanol and 38.9% for propanol at 1 kHz. The discontinuities or cracks present in the microstructure of the gate material are believed to be mainly responsible for the high sensitivity of the sensor, going with the decomposition of gas molecules and subsequent hydrogen permeation through Pd. 相似文献
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96.
Ajit Kumar Preeti Kaushik Sandra Incerpi Jens Z. Pedersen Sanjay Goel Ashok K. Prasad Vishwajeet Rohil Virinder S. Parmar Luciano Saso Christophe Len 《Molecules (Basel, Switzerland)》2021,26(16)
The purpose of this study was to examine the free radical scavenging and antioxidant activities of ellagic acid (EA) and ellagic acid peracetate (EAPA) by measuring their reactions with the radicals, 2,2-diphenyl-1-picrylhydrazyl and galvinoxyl using EPR spectroscopy. We have also evaluated the influence of EA and EAPA on the ROS production in L-6 myoblasts and rat liver microsomal lipid peroxidation catalyzed by NADPH. The results obtained clearly indicated that EA has tremendous ability to scavenge free radicals, even at concentration of 1 µM. Interestingly even in the absence of esterase, EAPA, the acetylated product of EA, was also found to be a good scavenger but at a relatively slower rate. Kinetic studies revealed that both EA and EAPA have ability to scavenge free radicals at the concentrations of 1 µM over extended periods of time. In cellular systems, EA and EAPA were found to have similar potentials for the inhibition of ROS production in L-6 myoblasts and NADPH-dependent catalyzed microsomal lipid peroxidation. 相似文献
97.
In this work, we have obtained energy levels and charge radius for the β-stability line nucleus, in relativistic shell model. In this model, we considered a close shell for each nucleus containing double magic number and a single nucleon energy level. Here we have taken 41Ca with a single neutron in the 40Ca core as an illustrative example. Then we have selected the Eckart plus Hulthen potentials for interaction between the core and the single nucleon. By using parametric Nikiforov–Uvarov (PNU) method, we have calculated the energy values and wave function. Finally, we have calculated the charge radius for 17O, 41Ca, 49Ca and 57Ni. Our results are in agreement with experimental values and hence this model can be applied for similar nuclei. 相似文献
98.
In this paper, the effect of nanostructures on the magnetic properties like the specific saturation magnetization (σS) and the coercivity (HC) for Mn0.4Zn0.6Fe2O4 ferrite prepared by the co-precipitation method has been presented. We have shown by means of X-ray diffraction that the resulting ferrite is made up of nanoparticles, and that the average size of these nanoparticles calculated with the Scherrer formula depends upon the sintering temperature. When the sintering temperature is increased from 500 to 900 °C, the average nanoparticle diameter varies from 19.3 to 36.4 nm. The nanoparticle phase is further confirmed by scanning electron microscopy (SEM). Both results are found to be in good agreement. The magnetic properties are explained on the basis of the single-domain and multi-domain theory. 相似文献
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100.
In this paper we show that over any field K of characteristic different from 2, the Maslov index gives rise to a 2-cocycle on the stable symplectic group with values in the Witt group. We also show that this cocycle admits a natural reduction to I
2(K) and that the induced natural homomorphism from K
2
Sp(K)I
2(K) is indeed the homomorphism given by the symplectic symbol {x, y} mapping to the Pfister form 1, -x 1, –y. 相似文献